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Polyvinyl acetate
| CASNo = 9003-20-7 | ChemSpiderID_Ref = | ChemSpiderID = none | PubChem = 7758 | KEGG_Ref = | KEGG = C12282 }} |Section2= |Section7= }} Poly(vinyl acetate) (PVA, PVAc, poly(ethenyl ethanoate): best known as wood glue, white glue, carpenter's glue, school glue, Elmer's glue in the US, or PVA glue) is an 脂肪族化合物 天然橡胶y 合成高分子 with the formula (C4H6O2)n. It belongs to the s family, with the general formula -RCOOCHCH2-. It is a type of 热塑性塑料. There is considerable confusion between the glue as purchased, an aqueous emulsion of mostly vinyl acetate monomer, and the subsequent dried and polymerized PVAc that is the true thermoplastic polymer. 特性 聚醋酸乙烯酯的聚合度一般在 100 到 5000，而其酯群對水解非常敏感，會緩慢的分解成為聚乙烯醇和乙酸。 PVAc emulsions such as contain polyvinyl alcohol as a protective colloid. In alkaline conditions, 硼 compounds such as 硼酸 or 硼砂 cause the polyvinyl alcohol to 交叉鏈接, forming tackifying precipitates or toys, such as 鬼口水 and . A number of microorganisms can degrade polyvinyl acetate. Most commonly, damage is caused by filamentous 真菌—however 藻類, 酵母s, 地衣s, and 细菌 can also degrade polyvinyl acetate. Discovery Poly(vinyl acetate) was discovered in 德国 in 1912 by .See: (1) Deutsche Reichs Patent no. 281687 (4 July 1913), Journal of the Society of Chemical Industry (London), vol. 34, page 623 (1915); (2) Deutsche Reichs Patent no. 281688 (2 April 1914); (3) British Patent no. 15271 (25 June 1914.); (4) Fritz Klatte and Adolf Rollett, "Plastic composition and process of producing it," U.S. Patent 1,241,738 (filed: July 3, 1914; issued: Oct. 2, 1917), an abstract of which appears in the Journal of the Society of Chemical Industry (London), vol. 36, page 1185 (1917). The monomer, 乙酸乙烯酯, was first produced on an industrial scale by the addition of 乙酸 to 乙炔 with a mercury(I) saltRutherford John Gettens and George Leslie Stout, Painting Materials: A Short Encyclopaedia (Princeton, New Jersey: D. Van Nostrand, 1942),page 74. but it is now primarily made by 钯 catalyzed oxidative addition of acetic acid to 乙烯. Preparation PVA is a vinyl polymer. Polyvinyl acetate is prepared by the 聚合 of 乙酸乙烯酯 (自由基 vinyl polymerization of the 单体 vinyl acetate). Applications As an 乳浊液 in water, PVAc emulsions are used as 黏合剂s for 孔隙率 materials, particularly for 木材, 纸, and 布, and as a consolidant for porous building stone, in particular 砂岩. Uses: * as , PVAc is known as "white glue" and the yellow as "carpenter's glue". * as paper adhesive during paper packaging conversion * in and book arts, due to its flexible strong bond and non-酸 nature (unlike many other polymers). The use of PVAc on the during the 20th century greatly hindered the task of disbinding the book and preserving and imaging the pages in the early 21st century, in part because the glue was stronger than the parchment it held together. |date=2011 |accessdate=February 22, 2018}} * in 手工艺 * as 封套 adhesive * as * as a 底漆 for 乾壁 and other substrates * as a gum base in 口香糖 The stiff 聚合物 PVAc, but mostly the more soft 共聚物, a combination of vinyl acetate and ethylene, 乙烯/醋酸乙烯酯共聚物 (VAE), is also used in 纸 coatings, 涂料 and other industrial coatings, as a binder in 不織布s in s, 衛生棉, 濾紙 and in . Polyvinyl acetate is also the raw material to make other polymers like: * 聚乙烯醇 -HOCHCH2-: Polyvinyl acetate is partially or completely 水解 to give polyvinyl alcohol. This reversible saponification and esterification reaction was a strong hint for 赫尔曼·施陶丁格 in the formulation of his theory of 高分子.H. Staudinger, K. Frey, W. Stark, Ber. Deut. Chem. Ges. 1927, 60, 1782. * (PVAP): Polyvinyl acetate is partially hydrolyzed and then esterified with 邻苯二甲酸. 參看 * 埃尔默胶 * 乙酸乙烯酯 * 聚乙烯醇 * Ethylene vinyl acetate * 聚合 * 國際奇連藍 參考文獻 外部連結 Category:黏合剂 Category:家用化学品 Category:乙烯聚合物 Category:高分子化合物 Category:乙酸酯 Category:有机高分子 Category:材料 Category:化学工业 Category:酯 J